The invention relates to a floatable flat textile structure, as well as to air-cushioning cables for such flat textile structure.
Conventional floating flat textile structures can be made, for example, of coated two-ply textile structures that are filled with air. Such structures tend to expensive since they consist of relatively finely-woven fabrics and, in addition, have to be coated.
DE 195 54 031 A1 proposes embedding tubes or hoses filled with air, resulting in a complicated assembly process, because the cut ends of the hollow members have to be closed. Moreover, the tubes or hoses of large-area structures may be accidentally damaged, allowing water to enter which decreases the buoyancy.
EP 0 666 364 A2 discloses a floating rope having a core made of expanded plastic material and a jacket made of textile threads laid on the core. This floating rope is quite stiff and thick and has a small bending radius, and is therefore unsuitable for use as a floatable flat textile structure.
In addition, WO 97/09481 discloses a floating rope having a core made of a center nylon rope, with a plurality of floating elements consisting of expanded plastic and so-called buffer elements, being arranged on the nylon rope. The outer jacket of the floating rope is formed of a protective layer made of polyurethane.
DE 36 34 307 A1 discloses a flat textile structure that includes a backing fabric made of warp threads in the form of stitch wales. The stitch wales are connected by weft threads. On one side of the backing fabric, a figure warp is applied to form the weft and the figure. The figure thread is connected at least over a section to the backing fabric by way of at least one stitch wale from an auxiliary weft thread. This arrangement produces a novel, versatile method for patterning the flat textile structure.
DE-OS 17 60 535 also describes floatable ropes. These ropes require an additional core made of parallel threads which together with the floatable components is surrounded by a relatively dense mesh or woven structure. The manufacture of such ropes is therefore quite inefficient. Other floating ropes are known that have cylindrical floating bodies arranged on the rope.
DD (WP) 11 64 79 also discloses a rope-like and cord-like product that can be used preferably in building construction for sealing cracks as well as in other applications, such as floating lines. In this rope construction, the floatable filler material is surrounded by a mesh structure composed of threads.
A cord and rope product having the aforedescribed features is known from EP 0 666 364 A2. The floating rope consists of two or more strands, wherein each of the strands has a core-jacket structure. The core is here formed as a floating body made of plastic tubes filled with an expanded plastic or a gas. Optionally, the tubes can have an occasional constriction along their longitudinal extent. Using a rope-laying technique, the form providing the buoyancy is surrounded with a plurality of textile threads having a substantial density and thickness. This prior art floating rope is relatively expensive to manufacture; moreover, the large number of textile threads which surround the floating body do not contribute to the buoyancy, but rather reduce the buoyancy.
It is therefore an object of the invention to provide a floating flat textile structure that has a high buoyancy, is not easily damaged, and can be manufactured cost-effectively.
According to one aspect of the invention, the floating bodies embedded in the floatable textile structure are air-filled ropes made of an air-filled foil, wherein the air-filled ropes are tied together with connecting elements.
The essential advantage of the floating flat textile structure according to the invention is that cord and cable products made of an air cushioning film, such as air cellular cushioning sold under the trademark Bubble Wrap(copyright) by Sealed Air Corporation of Saddle Brook, N.J. in the form of coarse threads provide a very high buoyancy. In addition, the flat textile structure is easy to assemble and inexpensive, because the cut ends of the air cushioning film do not have to be sealed. When the embedded air cushioning cables are locally damaged, only a relatively small loss of buoyancy can be expected due to the large number of air chambers within the air cushioning film. Moreover, the flat structure according to the invention is water-tight.
According to an embodiment of the invention, the flat structure of the invention includes an air cushioning cable formed as a strand-like air cushioning film, with the air cushioning film being surrounded by textile threads that protect the air cushioning film from mechanical damage. The textile threads can be arranged in the form of a mesh-type jacket with preferably widely spaced and coarse stitches.
Particularly compact floating cables with a high elastic cross-sectional compression characteristic can be manufactured by surrounding the strand-like air cushioning film directly with a coarse-mesh jacket made of threads that apply a constriction force to the air cushioning film in the radial direction.
According to another embodiment of the invention, the air cushioning film can be protected against the radiation effects by surrounding the air cushioning film with a UV protective film.
According to an advantageous embodiment, the air-filled ropes can be embedded either in a meander pattern or so as to extend in a longitudinal direction. The air-filled ropes can also be embedded in a composite material.
Additional objects, advantages, features and applications of the aforedescribed invention are described in the following description of embodiments when read in conjunction with the drawings. All the described and/or illustrated features alone or in combination represent the subject matter of the present invention, independent of their combination in the claims or their dependency.